The most common neoplasm of the larynx in children is the papilloma. Although classified histologically as a benign neoplasm this tumor has proved resistant to the current methods of surgical therapy. Spread in the larynx and seeding of the tumor along the respiratory tree are the result of uncontrolled disease. After a complete reappraisal of the disease a simultaneous tripartite investigation evolved; each part being closely interrelated and interdependent. Laryngeal papilloma cells have been propagated in tissue culture to provide an experimental model for assessment of the effectiveness of various types of immunotherapy. In addition this system provides material for further viral studies which is the second aspect of the study. Laryngeal papillomas are thought to be produced by the tumorigenic DNA containing virus belonging to the papova group. Viral isolation has not been reported from any human laryngeal papilloma although the virus has been isolated from several animal wart tissue and from human cutaneous papillomas. The distribution of papilloma viruses in skin warts indicated that they only replicate in the highly specialized cellular environment which may not exist in laryngeal papillomas. Various means will be tried to induce greater virus production in papilloma cells. Further, when sufficient viral antigen can be obtained the assay of antibody levels in patients will be facilitated. Preliminary data obtained from the above mentioned studies will be our guide to clinical treatment. Promising clinical response in patients with active disease has been obtained in our pilot study using transfer factor obtained from patients who have experienced spontaneous remission from their papilloma. It is the correlation of basic laboratory studies in virology and cell culture that has allowed and will allow future development of an effective immunological treatment of the clinical state. A successful completion of this proposed study would lead to the application of this methodology to other cancers.